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TL;DR

Scene Size-Up: Initial scene evaluation: safety, MOI/NOI, number of patients, additional resources needed, and C-spine consideration.

By Valenke Exam Prep Team·Last updated 2026-06-02

Scene Size-Up

NREMT EMTNREMT PARAMEDIC

Definition

Initial scene evaluation: safety, MOI/NOI, number of patients, additional resources needed, and C-spine consideration.

Step-by-Step Procedure

Protocol steps for scene size-up:

AHA ACLS cardiac arrest algorithm: CPR then rhythm check then shock if VF/pVT then epinephrine q3-5min then amiodarone

Differential Diagnosis

When assessing scene size-up, use structured assessment tools to differentiate between possible causes:

APGAR: Components: Appearance, Pulse, Grimace, Activity, Respiration. Scoring: 0-10 at 1 and 5 minutes, under 7 needs intervention.

SAMPLE: Components: Signs/symptoms, Allergies, Medications, Past history, Last intake, Events. Scoring: Mnemonic for patient history gathering.

Related Procedures

Procedures related to scene size-up in the EMS setting:

  1. AHA ACLS cardiac arrest algorithm: CPR then rhythm check then shock if VF/pVT then epinephrine q3-5min then amiodarone
  2. Pediatric weight-based dosing: Broselow tape for length-based weight estimation in emergencies

Key Values & Ranges

Key values and ranges relevant to scene size-up in prehospital care:

ParameterAdultPediatric
GCS15 is normal, under 8 = severe TBImodified pediatric GCS for preverbal
ETCO235-45 mmHg35-45 mmHg
blood pressure90/60-120/80 mmHg70+(2*age) systolic minimum
SpO295-100%95-100%

Why It Matters

Scene size-up is the first step of every EMT assessment. Tested on NREMT exam.

Related Terms

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Frequently Asked Questions

What assessment tools help evaluate scene size-up?
For scene size-up: Glasgow Coma Scale: evaluates Eye opening (1-4), Verbal response (1-5), Motor response (1-6); scoring is 3-15, 8 or less = severe, 9-12 = moderate, 13-15 = mild. APGAR: evaluates Appearance, Pulse, Grimace, Activity, Respiration; scoring is 0-10 at 1 and 5 minutes, under 7 needs intervention.
What equipment is needed for managing scene size-up in the field?
For scene size-up: BVM provides Bag-valve-mask for manual ventilation. King airway provides Supraglottic blind-insertion airway device. Pulse oximeter provides Measures SpO2 via infrared absorption through capillary bed.
What medications are commonly associated with scene size-up?
For scene size-up: albuterol: 2.5mg nebulized, can repeat, route Nebulized, for Bronchospasm, asthma, COPD. naloxone: 0.4-2mg IV/IM/IN, titrate to respirations, route IV, IM, IN, for Opioid overdose.